Nut-lock.



J. A. HARRIS.

NUT LOOK. APPLICATION I'ILED SEPT'. 19, 1910.

995; 1 36 1 Patented June 13, 1911.

JOSEPH A. HARRIS, OF BOSTON, MASSACHUSETTS.

NUT-LOCK Specification of Letters Patent.

Application filed September 19, 1910. Serial No. 582,783.

To all whom it may concern:

Be it known that I, JosErH'A. HARRIS, a citizen of the United States,residing at Boston, in the county of Suffolk and State of Massachusetts,have invented certain new and useful Im rovements in Nut-Locks; and I dohereby eclare' the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit appertains to make and use the same.

My invention relates to a torsional lock for bolts which can be embodiedeither in a self-locking nut adapted to hold itself in position on thebolt and against the surface upon which it bears or in an elasticyielding plate or washer adapted to be screwed upon the bolt, exteriorlyto the primary nut, and designed to bear upon the bolt threads and uponsaid primary nut to secure a compound frictional contact therewith.These results are due, first, to the increased friction attained betweenthe lock and the surface against which the lock bears, and, second tothe tendency of the threads in the torsional lock to cross the threadsof the bolt whereby a strong torsional resistance is produced betweenthe lock and the surface upon which it bears, and to grip upon the boltthreads so that the lock must remain immovable upon the bolt but, at thesame time, a yielding tension is provided for the restricted torsionallock which is very desirable, especially when the nut lock is used onmachinery and 'in fish-plates of rails which are subjected to jars andvibrations having a tendency to make the nuts Work loose.

The object of my present invention is to increase the efiiciency of thenut look by providing additional means which tend to bind the threads ofthe nut lock upon the threads of the bolt.

My improvement may be applied to either a flat locking-washer or plate,or to one that is concaved on the side next to the; primary the nut lockbears.

The threadsin the torsional lock are cut with their axes oblique to theaxis of said torsion look so that when the lock is screwed on the bolt,it will assume a diagonal position to the longitudinal axis of; thebolt, and, as it is screwed home a ainst the surface upon which it isdesigne to bear, said lock is deflected from its diagonal position to anut or metallic surface against which straight position parallel to andtightly against said bearing surf-ace. The tightening of the torsionallock against the primary nut or other bearing surface operates tocompress the outer threads of said lock Patented June 13, 1911.

against the threads of the bolt as the inner Y concave side of the lockis caused to spread or open out by increasing the frictional contact,that is to say, while the outer edges of the lock and its inner threadsare caused to spread at the concaved base of the lock, the

' outer threads thereof will be compressed and drawn together tightlyagainst the thread of the bolt. Furthermore, the diagonal threads in thelock cause the same to assume an inclined position on the bolt therebybringing one edge of the lock first in contact with the bearing surfaceso that, as the lock is screwed home against said surface, said lock isdeflected from its initial diagonal position to a position atrightangles to the axis of the bolt and parallel with the surface onwhich the lock bears, thus causing the threads of the lock to bind stillmore tightly and securely upon the threads of the bolt.

The lock possesses the additional and very desirable quality, when madein the form resistance which efi'ec-' designed to fasten a primary nut,but both the self-locking nut and the elastic washer can be used on thesame bolt to lock the nut itself on said bolt, or they can be used inconnection with a primary nut where greater strength and length ofthread are required for the bolt, as the improved self-locking nut actsas a very powerful and effective jam-nut.

The essential feature of the present improvement is one or more lugs orshoulders punched out on the side of the washer or plate. Two lugs isthe preferable number and they can be easily stamped'or punched out whenthe hole is cut and before the nut .lock is threaded. On a large bolt,it might nut lock is of uniform thickness except where the lugs project.It will be understood that the nut lock is reversible, that is, may beapplied to a bolt with either side facing the bearing surface or primarynut, except when the concaved form of nut lock is used, when theconcaved side must go next to the bearing surface or primarynut.

In forming the nut lock or washer, the shoulders or lugs can easily beformed by one operation when the hole is punched therein, or saidshoulders or projections may be made in any other suit-able manner. Thethread in the nut lock is extended on to the shoulders or lugs wherebyan additional binding area is rovided for engaging the thread of the b0t. The thread in the nut lock and its lugs may be formed in oneoperation by tapping right through said washer and lugs, itbeing'understood that this thread is arranged obliquely to the axis ofthe nut lock.

WVhen my improved nut lock is screwed upon a bolt, its inclinedposit-ion, with respect to the axis of said bolt, causes the lug orshoulder on the inner face of the nut lock to come in contact with thebearing surface or primary nut before the main inner surface of said nutlook. In tightening the washer, its inner shoulder or lug is brought tobear forcibly against the bearing'surface or primary nut and compressedto some extent .with the result that a kink is given to the washer aswell as the thread therein causing it to clamp very tightly upon thethread of the bolt without causing any rupture. At the same time, theouter lug on said nut lock is drawn in and caused to bind upon thethread of the bolt, as hereinbefore described, owing to the deflectingof said look from its initial diagonal position to a position at rightangles to the axis of the bolt. threads on said outer shoulder orprojection will bind more forcibly upon the threads of- In theaccompanying drawing illustrating the preferred embodiments of myinvention: Figure l is an elevation of a bolt with a primary nut and nutlock mounted thereon, the initial oblique position of the nut lockbeingshown in solid lines and its final position, at right angles to theaxis of the bolt and flat against the primary nut, being illustrated indotted'lines. Fig. 2 is a plan It is obvious, of course, that the viewof the nut lock alone. Fig, 3 is a sectional View, of said nutlock,,taken through the projecting lugs or shoulders. a similarsectional view of a concave washer, and Fig. 5 is a sectional view of abolt, primary nut and concave nut lock showing its initial obliqueposition in dotted lines and its final position in solid lines.

The nut lock disclosed herein should be made of mild steel of low carbonand of just sufficient flexibility to allow it to yield as it is screwedhome over a primary nut until it lies fiat against the latter. Said nutlock or washer 'may be made in any of the usual forms, but is preferablyhexagonal, as illustrated. The oppositely extending lugsor shoulders 2are formed on the washer 1 adjacent to the opening or hole 3 therein.The thread 4, which is cut oblique to the axis of the washer, iscontinued on said lugs.

In the drawing, 5 designates the bolt and 6 the primary nut. The primarynut is the equivalent of a metallic bearing surface or work againstwhich the nut lock may be used alone as a lock nut, as the action of thewasher is the same in either case.

In Figs. 4 and 5 of the drawing, 7 designates the concave washer, 8theoppositely extending shoulders formed thereon, and '9 the thread cuttherein; It will be noted in Fig. 5 how the outer face of the washer iscontracted around the thread of the bolt when said washer is screwed upto its final position at right angles to the axis of said bolt. This isshown by the difference in diameter of the outer .surface of the washer,as shown in solid and dotted lines.

By' the use of the projecting shoulders or lugs on my improved nutlock,I, in effect, obtain all the advantages, as far as clamping poweris concerned, of a much thicker washer. By reducing the thickness of thewasher, I not only secure the beneficial resiliency, especiallynecessary for a concave nut look, but also save metal in the manufactureof the washer, reduce the Weight thereof and provide a nut lock whichadmits of a minimum length of bolt. Because the thread of the bolt isnot injured by the use of my nut lock thereon, thelatter may be usedover again and reversed, if'desired.

Experiments have shown that the under shoulder of the steel washer beingharder than the iron nut, it will scrape, or'cut into, or embed itselfin the primary nut so that the washer can be forced down flat, causingan increased binding contact, thereby still more efiectually preventingany reverse movement of the washer except by the force of a wrench.

I do not limit myself to the details of construction herein describedand illustrated in the accompanying drawing but reserve the right tomake such changes as fairly fall within the scope of the appendedclaims.

Fig. 4 is the threads being continued on said shoulder for the purposespecified.

2. A nut lock, substantially as described, having the axis of itsthreads oblique to the axis of said lock, and provided with a lugonshoulder projecting from the inner face thereof adjacent to thethreaded opening therein, the threads being continued on said shoulderfor the purpose specified.

3. A nut lock, substantially as described, having the axis of itsthreads oblique to the axis of saidlock, and provided with a lug orshoulder projecting from the outer face thereof adjacent to the threadedopening therein, the threads being continued on said shoulder for thepurpose specified.

4. A nut lock, substantially as described, having the axis of itsthreads oblique to the axis of said lock, and provided with lugs orshoulders projecting from the opposite faces thereof, the threads beingcontinued on said shoulders for the purpose s ecified.

5. A nutlock, substantially as escribed, having the axis of its threadsoblique to the axis of said lock, and provided with a concavityextending from edge to edge of its inner face, and a shoulder projectingfrom said. concave face adjacent to the threaded opening therein, thethreads being continued on said shoulders for the purpose specified.

6. A nut lock, substantially as described, having the axis of itsthreads oblique to the axis of said lock, and provided with a concavityextending from edge to edge of its inner face, and a shoulder projectingfrom its outer face adjacent to the threaded opening therein, thethreads being continued on said shoulders for the purpose specified.

7. A nut lock, substantially as described, having the axis of itsthreads oblique to the axis of said lock, and provided with a concavityextending from edge to edge of its inner face, and shoulders projectingfrom the opposite faces thereof adjacent to the threaded openingtherein, the threads being continued on said shoulders for the purposespecified.

In testimony whereof, I afiix my signature,

in presence of two witnesses.

' JOSEPH A. HARRIS. Witnesses:

EDWARD P. BOYNTON, FRANCIS H. THAYER.

